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Jezzell490650
2012-02-02, 12:55 AM
First of all I'm a little new to using Least squares to balance a traverse with least squares. I believe that I figured out how to but I'm not sure how to read the report that civil 3d gives I have attached some of the report files and a copy of the fbk file. An help would be greatly appreciated.

mjfarrell
2012-02-02, 01:18 PM

Do Traverse Analysis
Select Yes to perform a mathematical analysis based on the method you specify as the Horizontal Adjustment Method.

Do Angle Balance
Select Yes to have the angular error evenly distributed throughout the traverse.

Least Squares: A method of balancing a traverse. The squares of the differences between the unadjusted and adjusted measurements (angles and distances) are summed and reduced to a minimum. This method weights the individual measurements according to the specifications set in the Equipment correction settings to determine the source of error. You can adjust the data for an individual traverse loop, or a traverse network, if located from multiple observations.
Least Squares: A method of distributing the vertical error throughout a traverse. The squares of the differences between the unadjusted and adjusted measurements (angles and distances) are summed and reduced to a minimum. This method weights the individual measurements according to the specifications set in the Equipment correction settings to determine the source of error. You can adjust the data for an individual traverse loop, or a traverse network, if located from multiple observations.
NoteThe Least squares vertical adjustment method is only available if Least squares has been selected as the horizontal adjustment method. When this method is selected, a 3D least squares adjustment is performed. If this method is not selected a 2D least squares adjustment is performed.
Horizontal Closure Limit 1:X
Specifies the minimum allowable error of closure in the horizontal direction, for example a value of 15000.00 is 1 part in 15000.

Vertical Closure Limit 1:X
Specifies the minimum allowable error of closure in the vertical direction, for example a value of 15000.00 is 1 part in 15000.

Angle Error Per Set
Specifics the maximum angular error per traverse setup.

Update Survey Database
Specify Yes to update the Survey database with the adjusted coordinates.

Note
During the analysis, if the specified limits for the horizontal, vertical, or angle limits are exceeded, a warning message box is displayed. Select Yes to update the database or No if you do not want the database updated.

In summary if you run the analysis, and chose to NOT update the database the reports will show you your what horizontal, and vertical adjustments would have been made using Least Squares to adjust the traverse for distance and vertical angle positioning errors.

If you update the database then the adjustments are applied to your traverse.

sinc
2012-02-09, 08:17 AM
To tell you the truth (AGH! I HATE that cliche), I would favor using Star*Net for this stuff, over C3D.

mjfarrell
2012-02-09, 11:56 AM
To tell you the truth (AGH! I HATE that cliche), I would favor using Star*Net for this stuff, over C3D.

OK...tell us some half truths.... ;)

As a Surveyor are there notable benefits over NOT using C3D for this operation?
If so, can you elaborate on them for us?